Why Mulan Jameela?

What's with 'ya iya lah ya iya dong mulan jameela mulan bla bla bla'?

In only the last one hour i came across this 'phrase' twice.

First, i was chitchating with a friend on YM. He said:

"ya iyalah di jkt,masa ya iya donk di jkt. kan mulan jameela, masa mulan jameedonk"

And second, i was blogwalking and stumble upon this blog. And he (I assume it belongs to a male blogger) said in one of his post:

"Ya iyalaah…..masak ya iya dunk, ya iyalah Mulan Jameelah, masak Mulan Jajiggong!!!"

OK, is this some kind of new 'bahasa gaul' nowadays?
But why Mulan Jameela?